Fermentation processes enzyme culturing

The content of desired enzymes at the end of fermentation processes should be as high as possible in order to ease the downstream processing. This may be achieved by a proper choice of microorganisms, optimising the fermentation conditions (e.g. culture media, inducer, morphology, growth rate) or by RDNA technology. 

These microorganisms are GRAS (general recognized as safe) and have widespread use in foods. Enzyme production can take place in their submerged fermentation (Figure 3.49) or surface culture (Koji) fermentation processes (Figure 3.50). 

In the future, novel developments of liquid membranes for biochemical processes should arise. There are several opportunities in the area of fermentation or cell culture, for the in situ recovery of inhibitory products, for example. Another exciting research direction is the use of liquid membrane for enzyme encapsulation so that enzymatic reaction and separation can be combined in a single step. Chapter 6 by Simmons ial- (49) is devoted to this technique. The elucidation of fundamental mechanisms behind the liquid membrane stability is essential, and models should be developed for the leakage rate in various flow conditions. Such models will be useful to address the effect of parameters such as flow regime, agitation rate, and microdroplet volume... 

The use of probiotic LAB, especially Lactobacillus and Bifidobacterium spp., as starter cultures, alone or in combination with traditional starter cultures in various fermentation processes, has been explored for different fermentation food products. Formulated fermented probiotic food may present consumers with a healthy dietary component at a considerabley low cost (Goldin, 1998). Furthermore, it was reported that LAB may contribute to microbiological safety and/or provide one or more technological, nutritional and organoleptic advantages to a fermented product, through production of ethanol, acetic acid, aroma compounds, exopolysaccharides, bacteriocins and several enzymes (Leroy De Vuyst, 2004). 

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